package org.runextbus.com.database;

import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

import android.content.Context;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteException;
import android.database.sqlite.SQLiteOpenHelper;

public class DataBaseHelper extends SQLiteOpenHelper{
 
    //The Android's default system path of your application database.
    private static String DB_PATH = "/data/data/org.runextbus.com/databases/";
 
    private static String DB_NAME = "RUBusPrediction.db";
 
    private SQLiteDatabase myDataBase; 
 
    private final Context myContext;
 
    /**
     * Constructor
     * Takes and keeps a reference of the passed context in order to access to the application assets and resources.
     * @param context
     */
    public DataBaseHelper(Context context) {
 
        super(context, DB_NAME, null, 1);
        this.myContext = context;
       
        //calling create database here 
        try {
                        createDataBase();
                } catch (IOException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                }
    }   
 
  /**
     * Creates a empty database on the system and rewrites it with your own database.
     * */
    public void createDataBase() throws IOException{
 
        boolean dbExist = checkDataBase();
      //  boolean dbExist = false;
 
        if(dbExist){
            System.out.println("Database exists !! \n");
                //do nothing - database already exist
        }
        
        else{
            System.out.println("I am here ... but did not kill your app !! \n");
                //By calling this method and empty database will be created into the default system path
               //of your application so we are gonna be able to overwrite that database with our database.
                this.getReadableDatabase();
 
                try {
 
                        copyDataBase();
 
                } catch (IOException e) {
 
                        throw new Error("Error copying database");
 
                }
        }
 
    }
 
    /**
     * Check if the database already exist to avoid re-copying the file each time you open the application.
     * @return true if it exists, false if it doesn't
     */
    private boolean checkDataBase(){
 
        SQLiteDatabase checkDB = null;
 
        try{
                String myPath = DB_PATH + DB_NAME;
                checkDB = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READONLY);
 
        }catch(SQLiteException e){
 
                //database does't exist yet.
 
        }
 
        if(checkDB != null){
 
                checkDB.close();
 
        }
 
        return checkDB != null ? true : false;
    }
 
    /**
     * Copies your database from your local assets-folder to the just created empty database in the
     * system folder, from where it can be accessed and handled.
     * This is done by transfering bytestream.
     * */
    private void copyDataBase() throws IOException{
 
        //Open your local db as the input stream
        InputStream myInput = myContext.getAssets().open(DB_NAME);
 System.out.println("Getting file from aSsets folder");
        // Path to the just created empty db
        String outFileName = DB_PATH + DB_NAME;

        //Open the empty db as the output stream
        OutputStream myOutput = new FileOutputStream(outFileName);
 
        //transfer bytes from the inputfile to the outputfile
        byte[] buffer = new byte[1024];
        int length;
        while ((length = myInput.read(buffer))>0){
                myOutput.write(buffer, 0, length);
        }
 
        //Close the streams
        myOutput.flush();
        myOutput.close();
        myInput.close();
 
    }
 
    public void openDataBase() throws SQLException{
 
        //Open the database
        String myPath = DB_PATH + DB_NAME;
        myDataBase = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READONLY);
 
    }
 
    @Override
        public synchronized void close() {
 
            if(myDataBase != null)
            myDataBase.close();
            super.close();
 
        }
 
        @Override
        public void onCreate(SQLiteDatabase db) {
 
        }
 
        @Override
        public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
 
        }
 
        // Add your public helper methods to access and get content from the database.
       // You could return cursors by doing "return myDataBase.query(....)" so it'd be easy
       // to you to create adapters for your views.



public class OpenHelper extends SQLiteOpenHelper {
                        
                 private final Context myContext;
                 
                 
         public OpenHelper(Context context) {
                        
                super(context, DB_NAME, null, 1);
                 this.myContext = context;
                 start();
          
                        
         }
         
         
         
void start(){
        
    DataBaseHelper myDbHelper=new DataBaseHelper(this.myContext);
        try {
                     
                        myDbHelper.createDataBase();
          
                } catch (IOException ioe) {
          
                        throw new Error("Unable to create database");
          
                }
          
                try {
          
                        myDbHelper.openDataBase();
          
                }catch(SQLException sqle){
          
                        throw sqle;
          
                }   
         
         }

        @Override
        public void onCreate(SQLiteDatabase db) {
                // TODO Auto-generated method stub

                
                
                
        }

        @Override
        public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
                // TODO Auto-generated method stub
                
        }       
           
}


public void closeDataBase()
{
    if(this.myDataBase != null)
    {
        if(this.myDataBase.isOpen())
            this.myDataBase.close();
    }
}   



}